Data commit

Task/Gamma-function/C-sharp/gamma-function.cs

@@ -0,0 +1,27 @@
+using System;
+using System.Numerics;
+
+static int g = 7;
+static double[] p = {0.99999999999980993, 676.5203681218851, -1259.1392167224028,
+	     771.32342877765313, -176.61502916214059, 12.507343278686905,
+	     -0.13857109526572012, 9.9843695780195716e-6, 1.5056327351493116e-7};
+		
+Complex Gamma(Complex z)
+{
+    // Reflection formula
+    if (z.Real < 0.5)
+	{
+        return Math.PI / (Complex.Sin( Math.PI * z) * Gamma(1 - z));
+	}
+    else
+	{
+        z -= 1;
+        Complex x = p[0];
+        for (var i = 1; i < g + 2; i++)
+		{
+            x += p[i]/(z+i);
+		}
+        Complex t = z + g + 0.5;
+        return Complex.Sqrt(2 * Math.PI) * (Complex.Pow(t, z + 0.5)) * Complex.Exp(-t) * x;
+	}
+}